Most vegetable gardens are watered as a whole unit according to seasonal elements such as wind and temperature.
Naturally, people realize vegetable plants increase their water demand as the temperature rises. Run-of-the-mill gardeners usually remove the guesswork out of watering by supplying as much water as their veggies can slurp up without drowning. From a conservation standpoint, this is wasteful.
From a yield standpoint, excessive watering is unnecessary and can aggravate pest problems.
Vegetables aren’t different from other plants in that they employ various strategies to locate and conserve water. Some crops, such as tomatoes, watermelons and sweet potatoes, have deep roots and can survive longer periods between irrigation cycles. Others, such as corn, radishes and strawberries, have shallow roots and dry out quickly when the water is cut off. Excessive watering can do more harm than good. Tomatoes are more likely to have disease problems when overwatered.
All vegetable crops need water during establishment. Once established, there are times they tolerate drought and times when water is critical. This variation in critical watering times is caused by crop differences in the timing of flowering, setting fruit and filling.
The critical watering period for tomatoes, watermelons, squash and eggplant is when the fruit is increasing in size. For cucumbers, cowpeas and cantaloupes, water should be steadily applied when they are flowering and developing fruit. Some vegetables, such as radishes, greens, collards and cabbage, need a steady supply of water throughout the season. Vegetables, such as carrots, parsnip, rutabagas and turnips, should be well-watered during root expansion.
Other water conserving practices include grouping crops according to the water requirements, using drip irrigation, and covering the soil with a three-inch layer of mulch. To learn more about vegetable growing and vegetable water requirements, call the Texas A&M AgriLife Extension Service at 432-498-4071.
